package com.juhui.gateway.filter;

import com.juhui.gateway.utils.WebFluxUtils;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.stereotype.Component;

import java.util.ArrayList;
import java.util.List;
import java.util.regex.Pattern;

/**
 * 黑名单过滤器
 *
 * @author melorogee
 */
@Component
public class BlackListUrlFilter extends AbstractGatewayFilterFactory<BlackListUrlFilter.Config> {
	@Override
	public GatewayFilter apply(Config config) {
		return (exchange, chain) -> {

			String url = exchange.getRequest().getURI().getPath();
			if (config.matchBlacklist(url)) {
				return WebFluxUtils.webFluxResponseWriter(exchange.getResponse(), "请求地址不允许访问");
			}

			return chain.filter(exchange);
		};
	}

	public BlackListUrlFilter() {
		super(Config.class);
	}

	public static class Config {
		private List<String> blacklistUrl;

		private List<Pattern> blacklistUrlPattern = new ArrayList<>();

		public boolean matchBlacklist(String url) {
			return !blacklistUrlPattern.isEmpty() && blacklistUrlPattern.stream().anyMatch(p -> p.matcher(url).find());
		}

		public List<String> getBlacklistUrl() {
			return blacklistUrl;
		}

		public void setBlacklistUrl(List<String> blacklistUrl) {
			this.blacklistUrl = blacklistUrl;
			this.blacklistUrlPattern.clear();
			this.blacklistUrl.forEach(url -> {
				this.blacklistUrlPattern.add(Pattern.compile(url.replaceAll("\\*\\*", "(.*?)"), Pattern.CASE_INSENSITIVE));
			});
		}
	}

}
